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1
18 package org.apache.activemq.transport.tcp;
19
20 import java.io.FilterInputStream  ;
21 import java.io.IOException ;
22 import java.io.InputStream ;
23
28 public class TcpBufferedInputStream extends FilterInputStream {
29 private static final int DEFAULT_BUFFER_SIZE=8192;
30 protected byte internalBuffer[];
31 protected int count;
32 protected int position;
33
34 public TcpBufferedInputStream(InputStream in){
35 this(in,DEFAULT_BUFFER_SIZE);
36 }
37
38 public TcpBufferedInputStream(InputStream in,int size){
39 super(in);
40 if(size<=0){
41 throw new IllegalArgumentException ("Buffer size <= 0");
42 }
43 internalBuffer=new byte[size];
44 }
45
46 private void fill() throws IOException {
47 byte[] buffer=internalBuffer;
48 count=position=0;
49 int n=in.read(buffer,position,buffer.length-position);
50 if(n>0)
51 count=n+position;
52 }
53
54 public int read() throws IOException {
55 if(position>=count){
56 fill();
57 if(position>=count)
58 return -1;
59 }
60 return internalBuffer[position++]&0xff;
61 }
62
63 private int readStream(byte[] b,int off,int len) throws IOException {
64 int avail=count-position;
65 if(avail<=0){
66 if(len>=internalBuffer.length){
67 return in.read(b,off,len);
68 }
69 fill();
70 avail=count-position;
71 if(avail<=0)
72 return -1;
73 }
74 int cnt=(avail<len)?avail:len;
75 System.arraycopy(internalBuffer,position,b,off,cnt);
76 position+=cnt;
77 return cnt;
78 }
79
80 public int read(byte b[],int off,int len) throws IOException {
81 if((off|len|(off+len)|(b.length-(off+len)))<0){
82 throw new IndexOutOfBoundsException ();
83 }else if(len==0){
84 return 0;
85 }
86 int n=0;
87 for(;;){
88 int nread=readStream(b,off+n,len-n);
89 if(nread<=0)
90 return (n==0)?nread:n;
91 n+=nread;
92 if(n>=len)
93 return n;
94 InputStream input=in;
96 if(input!=null&&input.available()<=0)
97 return n;
98 }
99 }
100
101 public long skip(long n) throws IOException {
102 if(n<=0){
103 return 0;
104 }
105 long avail=count-position;
106 if(avail<=0){
107 return in.skip(n);
108 }
109 long skipped=(avail<n)?avail:n;
110 position+=skipped;
111 return skipped;
112 }
113
114 public int available() throws IOException {
115 return in.available()+(count-position);
116 }
117
118 public boolean markSupported(){
119 return false;
120 }
121
122 public void close() throws IOException {
123 if(in!=null)
124 in.close();
125 }
126 }
127 |
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